In which of the following molecules/ions are all the bonds not equal?

If $E, M, J$ and $G$ respectively denote energy,mass,angular momentum,and universal gravitational constant,the quantity which has the same dimensions as the dimensions of $\frac{E J^2}{M^5 G^2}$ is:

Assertion : $LiCl$ is predominantly a covalent compound.
Reason : Electronegativity difference between $Li$ and $Cl$ is too small.

The magnetic needle of a vibration magnetometer makes $12$ oscillations per minute in the horizontal component of the earth's magnetic field. When an external short bar magnet is placed at some distance along the axis of the needle in the same line,it makes $15$ oscillations per minute. If the poles of the bar magnet are interchanged,the number of oscillations it makes per minute is

$A$ neutron makes a head-on elastic collision with a stationary deuteron. The fractional energy loss of the neutron in the collision is

The area (in sq. units) of the triangle formed by the lines $x^2-3xy+y^2=0$ and $x+y+1=0$ is